Heat oven to 220C/200C fan/gas 7, then put an empty muffin tin inside. Coarsely grate 1 large or 2 small courgettes and slice 4 spring onions. Heat 2 tsp rapeseed oil in a frying pan and fry the spring onions for about 3 mins. Stir in 1 crushed garlic clove and the grated courgette and cook for another 1 min, then set aside to cool.
Beat 3 large eggs, a good pinch dill fronds and 4 tbsp Greek yogurt together in a jug, then season. Stir in the courgette mixture. Take the muffin tin out of the oven and drop in eight muffin cases, divide the egg mixture between the cases and bake for 15-18 mins until set and golden. Serve hot or cold with salad.